Hospital-acquired infections (HAIs) significantly increase both the patient's length of stay and the cost of disease. For this reason, HAIs are one of the most important problems that intensive study is devoted to in many countries around the world. The purpose of this study is to investigate how having a HAI prolongs the length of stay and adds unnecessary cost to the patient. The study compared two matched groups and suggested that a patient with a HAI spent an additional 23 days in the hospital compared with a patient not affected with a HAI. The results also showed that a patient with a HAI had to pay more in almost all cost categories compared with a non-infected patient. The additional cost for an infected patient was calculated as US$2026.70. As a result of HAIs, the hospital had additional, but avoidable, expenses of US$30,754 for 57 patients over a period of four months.